Comparison between staggered and collocated grids in the finite-volume method performance for single and multi-phase flows

This work presents the numerical results obtained when staggered and collocated grids were used in the finite-volume methods (FVMs) for four standard flows: developing laminar single-phase flow at the entrance of the tube; developing turbulent single-phase flow at the entrance of the tube; incompressible laminar flow through an orifice plate; and developing turbulent gas–solid flow in a vertical pipe. These test cases were chosen to embody a variety of pattern flows very common in computational fluid dynamics problems (CFD problems). The main aspects analyzed were: the convergence rate, the stability of the pressure–velocity coupling; the dependence of the solution on the grid concentration and on the variation of the under-relaxation parameters; and the capability of reproduction of the experimental data and/or analytical solutions. The paper also presents a discussion of the strategies to apply the collocated and staggered grids and some aspects of the pressure–velocity coupling for both procedures. The numerical results were compared with experimental data or with analytical solutions and they presented a good agreement. The results show that the staggered arrangement of the grid has an advantage when dealing with high pressure gradient and multi-phase flows.